Good morning. My due date for my 90 day report is the 4th of Feb. which is Sunday. I haven't had luck with the online system here in Chiang Mai and have obligations which keep me from going to Immi today and Friday. I use a visa service at the Promenada and am entitled to 4 free reports with them. My question is whether there is a window past the the due date that I can do my report? Thanks!
TLDR : Answer Summary
In Thailand, the 90-day report can be submitted starting 15 days before the due date and up to 7 days after the due date without incurring any fines. If your due date is on a Sunday, you can file your report beginning from the previous month, and you have until the following Saturday to complete it.